Look, Mary has a new bike. How nice it is !—Yes. Her parents bought _____ for her progress in this exam. My parents also bought _____ for me for my improvement in English.

下面一段文字衔接最恰当的一组是①同时，舰体会携带某种拖曳式发音器在水中发出巨大的声响。②在这两根电缆通上电以后，就会在水中形成强大的电磁场。③各国军队在水中扫雷的方式基本大同小异。④除了大家熟悉的切割扫雷法之外，扫雷艇还用电磁和音响这两种扫雷方式。⑤沉底雷和浮雷的引信接收到这些磁场和声场信息后，就会自动上浮引爆。⑥电磁扫雷是指扫雷艇用两根长达数百米的电缆拖在舰后从需要扫雷的水面开过。

Professor Smith, along with his assistants, _________on the project day and night to meet the deadline

In case you ______ still have anything to offer, please contact our manager while he is available．

____ to light for a long time, the potatoes turned green.