10个句子,帮我检查下语法错误

10个句子,帮我检查下语法错误
1. When we finish this mission, we will have a big celebration.
2. Omar is a responsible boss, so every employee believes him.
3. We have to get assistance from government, otherwise, we will fail.
4. Steve has tried to fix the connector since two hours ago.
5. Steve cannot enter the laboratory because he is not belonging here.
6. Last night, my parents and I went to watch the performance in city centre, but both of us didn’t like it.
7. The government announced a command that all of the citizen should not attack animal.
8. When my girlfriend kissed I felt embarrass because my parents stood in front of me.
9. When we face dangers, our first reaction calls 911.
10. The commander gave a warning that all of the army should withdraw from the mountain last night.