1、题目108等差数列{an}的前3项和为15，且a1=2，则a2=( )

117、The party will be held in the garden， weather _________.

116、This machine is very easy _________ . Anybody can learn to use it in a few minutes.

115、--_____ does your cousin usually go to work on foot? --He says it＇s good for his health.

114、--Will Karen come to our party? --She hasn＇t decided yet.She _____ come.

113、-----Will you fix up the machine according to the _________， David? -----No problem.

112、-----How long is the bridge? -----It＇s _____.

111、His English is as _____ as his Chinese.

110、When you leave，please turn off the light _____ energy.

109、-----What were you doing when we were playing basketball yesterday afternoon? -----I _____ the classroom.

108、Teenagers should _____ to take care of themselves from a young age.