【单选题】The safety instruction cards concern the use of life jackets, oxygen( ) , emergency exits, rafts, and landing gear, etc., depending on the aircraft.
【简答题】Read the following paragraphs loudly.请大声朗读下面的段落 3 He then filled a cup with some of the petrol, some of the castor oil and some of the vinegar. As the students watched him quietly, he mixed the three ...