( )1yesterday,a man said he saw __UFO in the park.the police

( )1yesterday,a man said he saw __UFO in the park.the police are looking for ___UFO now.
A an,the B The,the C a,the D the,an
( )2 I Left My umbrella in My room.Could you wait ___I go back to get it?
A when B if C while D before
( )3 -what's wrong?
-I can't find my watch ____
A any where B somewhere C everywhere D nowhere
( )4 Keep The machine____,and you will know how it works
A run B to run C running D runs