Space Day of China falls________ April 24th every year.（ ）
A．onB．byC．atD．in
Tim is going to give his father a surprise ______ Father's Day．（ ）
A．inB．atC．onD．by
Ladies and gentlemen，attention please!I have ______ important to tell you．（ ）
A．nothingB．somethingC．everythingD．anything
I like hiking in the forest because the air is pretty ______．（ ）
A．freeB．dirtyC．pollutedD．fresh
﹣______ do you usually share happiness with？
﹣My parents and my best friend．（ ）
A．WhoB．WhoseC．WhatD．How
Nancy took her temperature and found she had a ______．（ ）
A．coughB．toothacheC．coldD．fever