If you are traveling ________ the customs are really foreign to your own，please do as the Romans do.
A．in which B．what
C．when D．where
Find ways to praise your children often，________ you’ll find they will open their hearts to you.
A．till B．or C．and D．but
Don’t be afraid of asking your teachers for help ________it is needed.
A．as B．since
C．unless D．when
The engineers are so busy that they have no time for outdoor sports activities，________ they have the interest.
A．wherever B．whenever
C．even if D．as if
In some places women are expected to earn money ________ men work at home and raise their children.
A．but B．while
C．because D．though
________ the fire breaks out，he is the first to arrive at the scene.
A．Every time when B．Moment
C．No matter whenever D．Every time
