By 1978, in the USA, the use of CFCs in aerosol propellants was banned.美国自1978年起禁止在喷雾剂压缩气体中使用含氯氟烃。This law closely resembles that obtained with conventional propellants.这种规律非常类似于用普通推进剂所得出的规律.The lighter version used liqu...
The lighter version used liquid hydrogen, the heavier used hypergolic propellants.较轻的推进器采用液态氢, 较重的采用自燃推进剂.Pressure - fed engines are particularly susceptible to dissolved gas in the propellants.挤压 式 发动机对推进剂中溶解的气体特别敏感.Thi...
Teachers often encourage class participation.教师常鼓励学生积极参与We agree to joint participation with you in chinese art and craft.我们同意和你们合资经营中国工艺品....orienting students to new ways of thinking about their participation in classr...
I mentioned this point by way of cautioning you.我提出了这一点用以警告你.All I'm doing is cautioning you.我没别的意思,只是提醒你而已.Sensible policymakers are cautioning that the world economy could weaken again before It'strengthens.理...
侍者把他们点的餐端了过来，格雷厄姆签了单。The waiter returned with their order and Graham signed the bill.众所周知，雷恩的墓志铭中写道，大教堂本身就是他的纪念碑。As Wren's epitaph famously declares, the cathedral itself is his monument.格雷丝轻轻敲了敲卧室的门，走了进去。Grace tapp...
杰克不会同意贾尼斯还在上学就结婚。Jake would not countenance Janis's marrying while still a student.贾尼斯和库尔特已宣布订婚。Janis and Kurt have announced their engagement.贾尼斯∙乔普林就是众所周知的摇滚乐大师。Janis Joplin was known as the High Priestess of Rock...
被惯坏的孩子总是为所欲为.A spoiled child wants his own way all the time.你会把孩子惯坏的——他总是为所欲为.You'll spoil that child — he always gets his own way.被惯坏的孩子常常是任性的.A spoiled child is often capricious....