英语翻译

英语翻译
1.In cross the section a pyramid is triangular.
2.They floated the raft down the riverw
3.We don’t normally have people over for dinner..
4.Fire on my command.
5.If you’re already in ____（contact）with the school,it will be easier to discuss any difficulties.
6.Reynolds was a notable conversationalist,well able to stand up to his friends.
7.The affair is greatly regretted by everyone concerned.
第五题是有括号里的词填空
每句翻译请指出词组或者为什么这样翻译的理由,句子要通顺,