【简答题】Rewrite the following sentences on the basis of general principles of business letter-writing : We request the favour of a reply at your earliest convenience.
【判断题】气相色谱和液相色谱是根据固定相的状态来分类的。
【判断题】气相色谱法和液相色谱法是根据流动相的不同分类的
【单选题】Directions: Rewrite the sentences replacing the long expressions with single words selected from the accompanying list . The name of the sender could not be found in any part of the letter The letter ...
【单选题】Directions: rewrite the sentences replacing the long expressions with single words selected from the accompanying list. The name of the sender could not be found in any poart of the letter. The letter...