Be and have

To talk about experiencing physical sensations like hunger, thirst, heat and cold, we use the structure be + adjective. Feel + adjective is also possible. Note that we do not usually use have + noun to express these ideas.

• I am hungry. (NOT I have hunger.)
• Are you thirsty? (NOT Do you have thirst?)
• Are you warm enough?
• I am sleepy.
• I am afraid.
• I feel hungry.
• I feel fine.
• I feel cold.

Note also the expressions:
Be right, be wrong and be lucky.

• You are right.
• He is lucky.
• Am I wrong?

Height, weight, age, size and color

Be, and not have, is used to talk about height, weight, age, size and color.

• She is nearly forty. (NOT She has nearly forty.)
• Her eyes are blue. (NOT Her eyes have blue.)
• My brother is six feet tall. (NOT My brother has six feet height.)
• She is the same height as her husband.
• What size are your shoes?
• I wish I was a few inches taller.
• I wish I was a few kilos lighter.

Note that in measuring expressions we do not use be heavy.

• She weighs forty-eight kilos. (NOT She is forty-eight kilos heavy.)

Note on the verb weigh
Weigh is one of those verbs which are not normally used in the progressive form.

• I weighed fifty-six kilos two months ago. (NOT I was weighing fifty-six kilos two months ago.)

However, weigh can be used in the progressive form when it does not mean ‘have weight’.

• The scales broke when she was weighing herself the other day.

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