He has been working since 7:30 this morning. ______ he is so tired out.

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

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

Each of the students, hoping to pass the exam, _____the book.

________ you stepped into the lab with your shoes on? You’re supposed to take them off before you enter it. I told you so!