act as circumstances dictate; act according to circumstances; adapt to changing circumstances; circumstances alter cases.; cope with any contingency; decide on the spot; hang up one's fiddle anywhere; trim the sail
Reacting with initiative to the unexpected is not a specialty of soviet diplomats . 苏联外交官没有那种临机应变、主动作出反应的特长。
2.
We would at least stick to the boat and give such minor service as chance might throw in the way . 我们至少要不离开船，而要临机应变，尽点小小的义务。
3.
Having no time to prepare , we resorted to using improvised props - our quan yin cloths . some wrapped them around their heads , and some tied them around their waists . forming a circle , we followed the rhythm and started to dance 在没有时间准备的情况下，大家只能临机应变，把身边的观音布当道具，有的绑在头上，有的系在腰上，围个圈，跟著节拍跳了起来。
4.
No sooner did he appear , than elizabeth wisely resolved to be perfectly easy and unembarrassed ; - a resolution the more necessary to be made , but perhaps not the more easily kept , because she saw that the suspicions of the whole party were awakened against them , and that there was scarcely an eye which did not watch his behaviour when he first came into the room 伊丽莎白见他走进来，便临机应变，下定决心，促使自己千万要表现得从容不迫，落落大方。她下定这个决心，确实很必要，只可惜事实上不大容易做到，因为她看到全场的人都在怀疑他们俩达西一走进来，几乎没有一只眼睛不在注意着他的举止。
