4th B3U3 vocab

vi. make a long low sound, e.g. because you are in pain or unhappy

v. speak about sth. in a way that shows you are unhappy

a. (fml.) creating problems for sb.

n. [C] a small group of people or things that are very close to each other

v. form a small close group

1) (+ a. / ad.) in a way that is impossible to doubt and easy to see

2) (BrE) in a way that shows you are very certain about sth.

a. sth. that is compulsory must be done because of a rule or law

vt. balance the effect of sth., with the result that there is no advantage or disadvantage

n. [U] the practice of flying planes

1) look at sb. or sth. for a period of time in a way that shows you are thinking

2) consider doing sth. in the future

1) fill sth. completely with a large number of things or a large amount of sth.

2) make sth. completely wet

1) very great in amount or degree

2) without limits in space or time