【简答题】离心泵的主要性能参数有()、压头、效率和轴功率。
【多选题】导游工作集体成员间相互协作、互相配合的基础是( )。
【单选题】A______ is a variety of a language that is not a native language of anyone, but is learned on contact situation such as trading.
【单选题】Which of the following statements CANNOT reflect the fragmentation of English?
A.
Non-native speakers are preferred to teach English in non-English-speaking countries.
B.
Many countries prefer to teach their mother tongues instead of English.
C.
The version of English taught by non-native teachers contains some features of their own language.
D.
Many more local English publications will appear.
【单选题】离心泵的主要性能参数有流量、扬程、功率和()四项。
【单选题】导游工作集体成员间相互协作、互相配合的基础是 。