The
auxiliary do is used mainly to form questions and negative
sentences with the present simple tense. It is not normally used
in affirmative sentences.
It
is also used in forming tag questions and shortened answers. Study
the following examples:
'I enjoy cycling in the countryside, but I don't enjoy
cycling in towns.'
'She doesn't play the ballgames that girls usually play,
but she plays football.'
'You don't really like Helen, do you?' 'Of course
I do! / No, it's true. I don't.'
'Do all cats drink milk?' 'Most do, some don't.'
'Doesn't he ever take a day off work?' 'He did once
in 1999, but he hasn't so far this year!'
Do
may be used in affirmative sentences, but when it is used in this
way, it denotes strong contrastive emphasis with heavy word stress
on the auxiliary itself.
Quite
a lot of emotion is usually involved. Study the following examples:
'Do come in! Please don't stand there on the doorstep.'
'He thinks I don't love him, but I do love him with
all my heart!'
'He's not a vegetarian! He does eat meat! I have seen
him eat meat!
did,
didn't
Past
simple auxiliary verbs
Did
and didn't are used as past simple 'helping' verbs in
exactly the same way as do/don't and does/doesn't are
used in the present simple.
Study
the following examples:
'I played a lot of rugby as a young man, but I didn't
ever play football.'
'You didn't forget to post my letter, did you?' 'Of
course I didn't.
'Did he pass his exam?' 'He did, yeah!'
'I did remember to put salt into the dishwasher. It's
not my fault that it's not working.'
have/haven't,
has/hasn't, had/hadn't
Present
perfect and past perfect auxiliary verbs
The
auxiliaries have and had are used as 'helping' verbs
in the construction of the perfect and past perfect forms of all
main verbs. They are often pronounced as contracted weak forms in
affirmative sentences and contracted weak forms are also used in
the negative. Study the following examples and say them to yourself
as you read them:
'They've been living in Calcutta for three years now,
but they still haven't got used to the heat.'
'He's collected his medication from the chemist, but he hasn't
actually taken any of the pills yet.'
'Have you seen my green pullover anywhere, Sandra?' 'No, sorry,
I haven't.'
'This was a lie, for she'd borrowed his green pullover
and had forgotten to return it.'
'They told me that they'd lived in Wiltshire all their
lives, but had never visited Stonehenge.'
'We have paid for the flights, but we haven't paid
the travel insurance yet.
Notice
that in this last example there is strong contrastive emphasis, so
the weak contracted form of have is not used in the affirmative
part of the utterance. This equates to the emphatic use of do in
the earlier examples.
