diff --git a/framework/src/Volo.Abp.MultiLingualObjects/Volo.Abp.MultiLingualObjects.csproj b/framework/src/Volo.Abp.MultiLingualObjects/Volo.Abp.MultiLingualObjects.csproj
index da83bc80f4..77da44eb47 100644
--- a/framework/src/Volo.Abp.MultiLingualObjects/Volo.Abp.MultiLingualObjects.csproj
+++ b/framework/src/Volo.Abp.MultiLingualObjects/Volo.Abp.MultiLingualObjects.csproj
@@ -1,20 +1,21 @@
-<Project Sdk="Microsoft.NET.Sdk">
-
-    <Import Project="..\..\..\configureawait.props" />
-    <Import Project="..\..\..\common.props" />
-
-    <PropertyGroup>
-        <TargetFramework>netstandard2.0</TargetFramework>
-        <PackageId>Volo.Abp.MultiLingualObject</PackageId>
-        <AssetTargetFallback>$(AssetTargetFallback);portable-net45+win8+wp8+wpa81;</AssetTargetFallback>
-        <GenerateAssemblyConfigurationAttribute>false</GenerateAssemblyConfigurationAttribute>
-        <GenerateAssemblyCompanyAttribute>false</GenerateAssemblyCompanyAttribute>
-        <GenerateAssemblyProductAttribute>false</GenerateAssemblyProductAttribute>
-        <RootNamespace />
-    </PropertyGroup>
-
-    <ItemGroup>
-      <ProjectReference Include="..\Volo.Abp.Localization\Volo.Abp.Localization.csproj" />
-    </ItemGroup>
-
-</Project>
+<Project Sdk="Microsoft.NET.Sdk">
+
+	<Import Project="..\..\..\configureawait.props" />
+	<Import Project="..\..\..\common.props" />
+
+	<PropertyGroup>
+		<TargetFramework>netstandard2.0</TargetFramework>
+		<PackageId>Volo.Abp.MultiLingualObject</PackageId>
+		<AssetTargetFallback>$(AssetTargetFallback);portable-net45+win8+wp8+wpa81;</AssetTargetFallback>
+		<GenerateAssemblyConfigurationAttribute>false</GenerateAssemblyConfigurationAttribute>
+		<GenerateAssemblyCompanyAttribute>false</GenerateAssemblyCompanyAttribute>
+		<GenerateAssemblyProductAttribute>false</GenerateAssemblyProductAttribute>
+		<RootNamespace />
+		<Nullable>enable</Nullable>
+	</PropertyGroup>
+
+	<ItemGroup>
+		<ProjectReference Include="..\Volo.Abp.Localization\Volo.Abp.Localization.csproj" />
+	</ItemGroup>
+
+</Project>