Not "He work in an office." — say "He works in an office.". The -s is what tells you it is he, she, or it.
Try it: He ___ in an office. (works / work / working) Answer: works — With he, the verb takes -s: He works. work is the form for I, you, we and they, and working never stands on its own after he.
He / she / it: -es spelling
When the verb ends in s, x, ch, or sh, the ending is -es. Two more to learn by heart: go → goes and do → does.
She watches movies.
He pushes the door.
She fixes the car.
He goes to work.
Try it: She ___ movies. (watches / watchs / watch) Answer: watches — After ch the ending is -es, not -s: watches. watchs has the right idea with the wrong ending, and watch has no ending at all, which is the form for I, you, we and they.
He / she / it: -ies spelling
Look at the pattern: study → studies · try → tries · fly → flies. The y becomes ies. But if a, e, i, o, or u comes right before the y, keep the y and just add -s: play → plays.
She studies English.
He tries hard.
but: play → plays (an a before the y)
Try it: She ___ English every day. (studies / studys / study) Answer: studies — Close, the y changes: study → studies (not "studys").
doesn't + verb
With he, she, it, say no with doesn't. The change goes into doesn't, so the verb after it stays plain.
He doesn't work here.
She doesn't live in Haffenville.
It doesn't cost ten dollars.
Not "She doesn'tlives here." — say "She doesn'tlive here.". doesn't already shows you it is she, so the next word is the plain verb.
Try it: Hiroshi ___ a jacket. It is very hot. (doesn't wear / doesn't wears / don't wear) Answer: doesn't wear — Hiroshi is he, so the negative is doesn't plus the plain verb: doesn't wear. doesn't wears puts the ending on the verb as well, and don't wear is the form for I, you, we and they.
Does she...?
To ask about an action with he, she, it, start with Does, then the person, then the plain verb.
Does he work here?
Does she live in Haffenville?
Does it cost ten dollars?
Not "Does he works here?" — say "Does he work here?". Does already shows you it is he, so the next word is the plain verb.
Try it: ___ Camila buy her clothes at Mosh Market? (Does / Do / Is) Answer: Does — Camila is she, so the question opens with Does. Do is for I, you, we and they, and Is opens a question about a describing word or a thing, not an action.
Yes, she does. / No, she doesn't.
A question that opens with Does comes back in the answer as does or doesn't. You know this from Yes, I do.: the same word that starts the question ends the answer.
Does she cook dinner? - Yes, she does.
Does he study at home? - No, he doesn't.
Does it open at nine? - Yes, it does.
Not "Does she cook dinner? - Yes, she cooks." — say "Does she cook dinner? - Yes, she does.". The short answer keeps does, so you do not have to say the verb again.
Try it: Amina: Does Hiroshi walk to Mosh Market? Sofia: ___ His house is next to it. (Yes, he does. / Yes, he do. / Yes, he is.) Answer: Yes, he does. — The question opens with Does, so the answer brings does back. do is the form for I, you, we and they, and is answers a question that opened with Is.
has / doesn't have / Does she have...?
You know She has a bike. To say no and to ask, doesn't and Does do the work, and has goes back to plain have.
She has a bike.
She doesn't have a bike.
Does she have a bike?
Not "She doesn't has a bike." — say "She doesn't have a bike.". doesn't already shows you it is she, so the next word is plain have.
Try it: Ira: Does Liam's apartment have three bedrooms? Amina: No, it ___ three. It has two. (doesn't have / doesn't has / don't have) Answer: doesn't have — The apartment is it, so the negative is doesn't plus plain have. doesn't has keeps the ending on the verb as well, and don't have is the form for I, you, we and they.
Try it: Wei: ___ Matilda have a big kitchen in her house? Lani: Yes, she does. She cooks dinner for her friends there. (Does / Has / Is) Answer: Does — Matilda is she, so the question opens with Does and have stays plain after it. Has puts the ending at the front instead of using Does, and Is opens a question about what someone is like, not about what they have.
Which ending?
Before each verb, ask: who? he/she/it → add -s. I/you/we/they → no ending.
He plays. / They play.
She works. / We work.
Not "He play. / They plays." — say "He plays. / They play.". Same verb, the subject decides the ending.
Try it: My sister ___ tea, but my parents ___ coffee. (drinks … drink / drink … drinks / drinks … drinks) Answer: drinks … drink — My sister = she → drinks (-s). My parents = they → drink (no ending).
Try it: My brother ___ in a bank, but his friends ___ in a shop. (works … work / work … works / works … works) Answer: works … work — My brother = he → works (-s). His friends = they → work (no ending). Who does it decides each one.