Mary's birthday is coming.We've decided to make a cake for_________.（　　）

A．himB．herC．youD．them

Space Day of China falls________ April 24th every year.（　　）

A．onB．byC．atD．in

—______shall we meet for the picnic？

—At the school gate.（　　）

A．HowB．WhenC．WhyD．Where

—Sam，_________I join you in the community service？

—Of course you can.（　　）

A．canB．mustC．shouldD．need

The doctors worked for ten hours，___________nobody took a break.（　　）

A．soB．forC．butD．or