diff --git a/mirai-api-http/src/main/kotlin/net/mamoe/mirai/api/http/route/GroupManageRouteModule.kt b/mirai-api-http/src/main/kotlin/net/mamoe/mirai/api/http/route/GroupManageRouteModule.kt
index 645cb741e..21e4fe021 100644
--- a/mirai-api-http/src/main/kotlin/net/mamoe/mirai/api/http/route/GroupManageRouteModule.kt
+++ b/mirai-api-http/src/main/kotlin/net/mamoe/mirai/api/http/route/GroupManageRouteModule.kt
@@ -19,12 +19,12 @@ fun Application.groupManageModule() {
          * 禁言（需要相关权限）
          */
         miraiVerify<MuteDTO>("/muteAll") {
-            it.session.bot.getGroup(it.target).muteAll = true
+            it.session.bot.getGroup(it.target).isMuteAll = true
             call.respondStateCode(StateCode.Success)
         }
 
         miraiVerify<MuteDTO>("/unmuteAll") {
-            it.session.bot.getGroup(it.target).muteAll = false
+            it.session.bot.getGroup(it.target).isMuteAll = false
             call.respondStateCode(StateCode.Success)
         }
 
@@ -65,8 +65,8 @@ fun Application.groupManageModule() {
             with(dto.config) {
                 name?.let { group.name = it }
                 announcement?.let { group.entranceAnnouncement = it }
-                confessTalk?.let { group.confessTalk = it }
-                allowMemberInvite?.let { group.allowMemberInvite = it }
+                confessTalk?.let { group.isConfessTalkEnabled = it }
+                allowMemberInvite?.let { group.isAllowMemberInvite = it }
                 // TODO: 待core接口实现设置可改
 //                autoApprove?.let { group.autoApprove = it }
 //                anonymousChat?.let { group.anonymousChat = it }
@@ -128,8 +128,8 @@ private data class GroupDetailDTO(
     val anonymousChat: Boolean? = null
 ) : DTO {
     constructor(group: Group) : this(
-        group.name, group.entranceAnnouncement, group.confessTalk, group.allowMemberInvite,
-        group.autoApprove, group.anonymousChat
+        group.name, group.entranceAnnouncement, group.isConfessTalkEnabled, group.isAllowMemberInvite,
+        group.isAutoApproveEnabled, group.isAnonymousChatEnabled
     )
 }
 
diff --git a/mirai-core-qqandroid/src/commonMain/kotlin/net/mamoe/mirai/qqandroid/ContactImpl.kt b/mirai-core-qqandroid/src/commonMain/kotlin/net/mamoe/mirai/qqandroid/ContactImpl.kt
index 259fe6591..a933dcfdf 100644
--- a/mirai-core-qqandroid/src/commonMain/kotlin/net/mamoe/mirai/qqandroid/ContactImpl.kt
+++ b/mirai-core-qqandroid/src/commonMain/kotlin/net/mamoe/mirai/qqandroid/ContactImpl.kt
@@ -394,7 +394,7 @@ internal class GroupImpl(
         }
 
 
-    override var allowMemberInvite: Boolean
+    override var isAllowMemberInvite: Boolean
         get() = _allowMemberInvite
         set(newValue) {
             this.checkBotPermissionOperator()
@@ -414,19 +414,19 @@ internal class GroupImpl(
             }
         }
 
-    override var autoApprove: Boolean
+    override var isAutoApproveEnabled: Boolean
         get() = _autoApprove
         set(newValue) {
             TODO()
         }
 
-    override var anonymousChat: Boolean
+    override var isAnonymousChatEnabled: Boolean
         get() = _anonymousChat
         set(newValue) {
             TODO()
         }
 
-    override var confessTalk: Boolean
+    override var isConfessTalkEnabled: Boolean
         get() = _confessTalk
         set(newValue) {
             this.checkBotPermissionOperator()
@@ -447,7 +447,7 @@ internal class GroupImpl(
         }
 
 
-    override var muteAll: Boolean
+    override var isMuteAll: Boolean
         get() = _muteAll
         set(newValue) {
             this.checkBotPermissionOperator()
diff --git a/mirai-core-qqandroid/src/commonMain/kotlin/net/mamoe/mirai/qqandroid/network/protocol/packet/chat/receive/OnlinePush.kt b/mirai-core-qqandroid/src/commonMain/kotlin/net/mamoe/mirai/qqandroid/network/protocol/packet/chat/receive/OnlinePush.kt
index 5b2bd3fe2..87afe2054 100644
--- a/mirai-core-qqandroid/src/commonMain/kotlin/net/mamoe/mirai/qqandroid/network/protocol/packet/chat/receive/OnlinePush.kt
+++ b/mirai-core-qqandroid/src/commonMain/kotlin/net/mamoe/mirai/qqandroid/network/protocol/packet/chat/receive/OnlinePush.kt
@@ -180,14 +180,14 @@ internal class OnlinePush {
                                     return if (target == 0L) {
                                         if (time == 0) {
                                             GroupMuteAllEvent(
-                                                origin = group.muteAll.also { group._muteAll = false },
+                                                origin = group.isMuteAll.also { group._muteAll = false },
                                                 new = false,
                                                 operator = operator,
                                                 group = group
                                             )
                                         } else {
                                             GroupMuteAllEvent(
-                                                origin = group.muteAll.also { group._muteAll = true },
+                                                origin = group.isMuteAll.also { group._muteAll = true },
                                                 new = true,
                                                 operator = operator,
                                                 group = group
@@ -213,7 +213,7 @@ internal class OnlinePush {
                                     val operator = group[this.readUInt().toLong()]
                                     val switch = this.readInt() == 0
                                     return GroupAllowAnonymousChatEvent(
-                                        origin = group.anonymousChat.also { group._anonymousChat = switch },
+                                        origin = group.isAnonymousChatEnabled.also { group._anonymousChat = switch },
                                         new = switch,
                                         operator = operator,
                                         group = group
@@ -236,7 +236,7 @@ internal class OnlinePush {
                                         when (message) {
                                             "管理员已关闭群聊坦白说" -> {
                                                 return GroupAllowConfessTalkEvent(
-                                                    origin = group.confessTalk.also { group._confessTalk = false },
+                                                    origin = group.isConfessTalkEnabled.also { group._confessTalk = false },
                                                     new = false,
                                                     group = group,
                                                     isByBot = false
@@ -244,7 +244,7 @@ internal class OnlinePush {
                                             }
                                             "管理员已开启群聊坦白说" -> {
                                                 return GroupAllowConfessTalkEvent(
-                                                    origin = group.confessTalk.also { group._confessTalk = true },
+                                                    origin = group.isConfessTalkEnabled.also { group._confessTalk = true },
                                                     new = true,
                                                     group = group,
                                                     isByBot = false
diff --git a/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/contact/Contact.kt b/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/contact/Contact.kt
index 42a96bec4..80c2900bc 100644
--- a/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/contact/Contact.kt
+++ b/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/contact/Contact.kt
@@ -38,8 +38,8 @@ interface Contact : CoroutineScope {
     /**
      * 可以是 QQ 号码或者群号码.
      *
-     * 对于 QQ, `uin` 与 `id` 是相同的意思.
-     * 对于 Group, `groupCode` 与 `id` 是相同的意思.
+     * 对于 [QQ], `uin` 与 `id` 是相同的意思.
+     * 对于 [Group], `groupCode` 与 `id` 是相同的意思.
      */
     val id: Long
 
diff --git a/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/contact/Group.kt b/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/contact/Group.kt
index b5dace4d2..c705ef844 100644
--- a/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/contact/Group.kt
+++ b/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/contact/Group.kt
@@ -46,8 +46,9 @@ interface Group : Contact, CoroutineScope {
      * 当前仅能修改状态.
      *
      * @see GroupMuteAllEvent
-     */// TODO: 2020/2/5 实现 muteAll 的查询
-    var muteAll: Boolean
+     * @throws PermissionDeniedException 无权限修改时将会抛出异常
+     */
+    var isMuteAll: Boolean
     /**
      * 坦白说状态. `true` 为允许.
      *
@@ -56,7 +57,7 @@ interface Group : Contact, CoroutineScope {
      * @see GroupAllowConfessTalkEvent
      * @throws PermissionDeniedException 无权限修改时将会抛出异常
      */
-    var confessTalk: Boolean
+    var isConfessTalkEnabled: Boolean
     /**
      * 允许群员邀请好友入群的状态. `true` 为允许
      *
@@ -65,15 +66,15 @@ interface Group : Contact, CoroutineScope {
      * @see GroupAllowMemberInviteEvent
      * @throws PermissionDeniedException 无权限修改时将会抛出异常
      */
-    var allowMemberInvite: Boolean
+    var isAllowMemberInvite: Boolean
     /**
      * 自动加群审批
      */
-    val autoApprove: Boolean
+    val isAutoApproveEnabled: Boolean
     /**
      * 匿名聊天
      */
-    val anonymousChat: Boolean
+    val isAnonymousChatEnabled: Boolean
 
     /**
      * 同为 groupCode, 用户看到的群号码.
diff --git a/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/contact/Permission.kt b/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/contact/Permission.kt
index c064535e6..ac1137744 100644
--- a/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/contact/Permission.kt
+++ b/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/contact/Permission.kt
@@ -72,9 +72,9 @@ inline fun Member.isOperator(): Boolean = this.permission.isOperator()
 /**
  * 权限不足
  */
-class PermissionDeniedException : IllegalStateException {
-    constructor() : super("Permission denied")
-    constructor(message: String?) : super(message)
+expect class PermissionDeniedException : IllegalStateException {
+    constructor()
+    constructor(message: String?)
 }
 
 @UseExperimental(MiraiExperimentalAPI::class)
diff --git a/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/event/events/BotEvents.kt b/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/event/events/BotEvents.kt
index 9047df8e0..a855e40b2 100644
--- a/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/event/events/BotEvents.kt
+++ b/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/event/events/BotEvents.kt
@@ -22,11 +22,11 @@ import net.mamoe.mirai.utils.MiraiExperimentalAPI
 
 
 @Suppress("unused")
-class EventCancelledException : RuntimeException {
-    constructor() : super()
-    constructor(message: String?) : super(message)
-    constructor(message: String?, cause: Throwable?) : super(message, cause)
-    constructor(cause: Throwable?) : super(cause)
+expect class EventCancelledException : RuntimeException {
+    constructor()
+    constructor(message: String?)
+    constructor(message: String?, cause: Throwable?)
+    constructor(cause: Throwable?)
 }
 
 // note: 若你使用 IntelliJ IDEA, 按 alt + 7 可打开结构