1.I'll never forget such an attractive city___I spent many h

1.I'll never forget such an attractive city___I spent many happy hours there with my classmates last summer holidays.
A.that B.where C.in which D.because
2.In hot weather,an old tyre can break again easily___it's mended.
A.when B.where C.which D.that
3.I won't give you such help___you tell me the truth.It's beyond my ability.
A.when B.since C.if D.even if
4.Most birds find it safe to sleep in the trees,so___they have eggs or young chicks,they don't use a nest.
A.why B.how C.where D.unless
5.-Was it there___you were away to answer the phone?
-There is no doubt about it.
A.that B.which C.while D.where
6.When solving the problem a second time,you'd better be more careful__you made a mistake.
A.in case B.where C.in which D.that
7.They kept trying___they must have known it was hopeless.
A.if B.because C.when D.where
8.Many adults agree that teenagers shouldn't alone___they have their parent's permission.
A.if B.unless C.in case D.now that
9.Jenny was very sad over the loss of the photos she had shot in Canada,___this was a memory she especially treasured.
A.as B.if C.when D.where
10.___there is a snowstorm or some other bad weather,the mail always comes on time.
A.Because B.If C.When D.Unless
11.-How do you think I should receive the visitor?
-___you feel about him,try to be polite.
A.No matter B.How C.Whatever D.However
12.We must think twice___we make the final decision.
A.when B.while C.until D.before
13.Several years had passed____I finally realized the true value of friendship.
A.when B.that C.before D.until
14.___the quality of schooling is high,parents are eager not only to send their chilren to school,but also to___them there.
A.Where,keep B.Where,leave C.When.keep D.When,leave
15.My mother likes everything in order,and she always reminds us to put things back____we get them from.
A.so that B.in which C.once D.where
16.Janet spent momey___there were no tomorrow.
A.even though B.though C.as though D.if only

B C A D C C B B D A C D B A C D