It is necessary for the ship to contact ____ for authorization prior to undertaking mitiga

However, where immediate action is necessary to ensure safety of the ship, its machinery and crew, it must be taken by the engineer in chargeWhat dose “it” mean in the sentence above？

It is quite necessary for a qualified teacher to

Is it necessary for me to attend the meeting？（英译中)

Is it necessary （)the book immediately？A．for him to returnB．that he returnsC．his returni

According to Paragraph 5, which of the following is CORRECT？A．It is necessary to look for

The life boat______in case it is necessary to take off the crew of the damaged ship.A．has