Tra từ half - Từ điển Oxford Advanced Learner 8th

half [half halves] noun, determiner, pronoun, adverb BrE [hɑːf] NAmE [hæf]
noun (pl. halvesBrE [hɑːvz] ; NAmE [hævz] )
1. either of two equal parts into which sth is or can be divided
•two and a half kilos (2½)
• One and a half hours are allowed for the exam.
• An hour and a half is allowed for the exam.
•The second half of the book is more exciting.
•I've divided the money in half.
•We'll need to reduce the weight by half.
see also ↑halve
2. either of two periods of time into which a sports game, concert, etc. is divided
• No goals were scored in the first half.
3. = ↑halfback
see also ↑centre half, ↑scrum half
4. (BrE, informal)half a pint of beer or a similar drink
• Two halves of bitter, please.
more at have half a mind to do sth at ↑mind _n., it's six of one and half a dozen of the other at ↑six, time and a half at ↑time _n.

Word Origin:
Old English half, healf, of Germanic origin; related to Dutch half and German halb (adjectives). The earliest meaning of the Germanic base was ‘side’, also a noun sense in Old English.

Grammar Point:
half / whole / quarter
Quarter, half and whole can all be nouns: ▪ Cut the apple into quarters. ◇ ▪ Two halves make a whole.
Whole is also an adjective: ▪ I’ve been waiting here for a whole hour.
Half is also a determiner: ▪ Half (of) the work is already finished. ◇ ▪ They spent half the time looking for a parking space. ◇ ▪ Her house is half a mile down the road. Note that you do not put a or the in front of half when it is used in this way: ▪ I waited for half an hour ◇ I waited for a half an hour.
Half can also be used as an adverb: ▪ This meal is only half cooked.

Example Bank:
•Costs rose by a half.
•Cut the remaining half into large chunks.
•He played well in the second half of the match.
•Over a half of all accidents happen in the home.
•Over a half of all the people interviewed said they were disappointed in the government.
•She's four and a half years old now.
•We divided the money in half.
•We split the work half and half.
•You'll have to ask my other half.
•in the latter half of the 19th century
•the first half of the concert
•the left half of the brain
•the lower half of the window
•the northern half of the country
•the rear half of the car
Idioms: ↑and a half ▪ ↑do not do anything by halves ▪ ↑go half and half ▪ ↑go halves ▪ ↑half a loaf is better than no bread ▪ half a minute/second ▪ half as many/much again ▪ ↑half of it ▪ half past one/two ▪ ↑how the other half lives ▪ ↑not half ▪ ↑not half as ▪ ↑not half bad ▪ ↑not half such a ▪ ↑too clever by half

determiner, pronoun
1. an amount equal to half of sth/sb
•half an hour
•Half (of) the fruit was bad.
• Half of the money was mine.
• He has a half share in the company.
•Out of 36 candidates, half passed.
2. ~ the time, fun, trouble, etc. the largest part of sth
•Half the fun of gardening is never knowing exactly what's going to come up.
•Half the time you don't even listen to what I say.

Word Origin:
Old English half, healf, of Germanic origin; related to Dutch half and German halb (adjectives). The earliest meaning of the Germanic base was ‘side’, also a noun sense in Old English.

Grammar Point:
half / whole / quarter
Quarter, half and whole can all be nouns: ▪ Cut the apple into quarters. ◇ ▪ Two halves make a whole.
Whole is also an adjective: ▪ I’ve been waiting here for a whole hour.
Half is also a determiner: ▪ Half (of) the work is already finished. ◇ ▪ They spent half the time looking for a parking space. ◇ ▪ Her house is half a mile down the road. Note that you do not put a or the in front of half when it is used in this way: ▪ I waited for half an hour ◇ I waited for a half an hour.
Half can also be used as an adverb: ▪ This meal is only half cooked.

Language Bank:
proportion
Describing fractions and proportions
▪ According to this pie chart, a third of ▪ students' leisure time is spent watching TV.
One in five ▪ hours is/are spent socializing.
▪ Socializing accounts for ▪ / makes up ▪ / comprises ▪ about 20% of leisure time.
▪ Students spend twice as much ▪ time playing computer games as doing sport.
Three times as many ▪ hours are spent playing computer games as reading.
▪ The figure for playing computer games is three times higher than ▪ the figure for reading.
The largest proportion of ▪ time is spent playing computer games.
note at ↑half
Synonyms at ↑consist
Language Banks at ↑expect, ↑fall, ↑illustrate, ↑increase

adverb
1. to the extent of half
• The glass was half full.
2. partly
• The chicken was only half cooked.
•half-closed eyes
• I'm half inclined to agree.

Word Origin:
Old English half, healf, of Germanic origin; related to Dutch half and German halb (adjectives). The earliest meaning of the Germanic base was ‘side’, also a noun sense in Old English.

Example Bank:
•His left eye was half closed.
•I half expected them to follow us.
•I was still half asleep.
•She is half Italian.
•The bottle was only half full.
•The child looked half starved.
•The result was not half as bad as expected.

See also: half after one/two ▪ ↑half again as much ▪ half one/two