An early typewriter produced letters quickly and neatly; the typist, _____ couldn't see his work on his machine.
| A．however | B．therefore | C．yet | D．although |
________tomorrow，our ship will set sail for Macao.
| A．However the weather is like |
| B．However is the weather like |
| C．Whatever is the weather like |
| D．Whatever the weather is like |
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 |