_____ is no doubt ______ you have to remain seated and fasten your seatbelt before the plane lands.

There is no _______ that drinking milk before going to bed is helpful to our health.

What does it ________ if I spend $ 100 on it ---it’s my money.

(2013·江西重点中学一次联考)________ was known to them that the boss had broken his promise ________ he would give them a rise.

He is rather difficult to make friends with, but his friendship, _____, is more true than any other.