^{Choose the correct form of the verb in "SIMPLE PRESENT TENSE":}
The scientist __________ (discover) new elements for his research.

• discovered
• discovering
• discovers

Answer explanation

"The scientist" is a singular subject, so we add "-s" to the base verb "discover." The simple present tense rule applies: He/She/It + verb (s/es).

^{Choose the correct form of the verb in "SIMPLE PRESENT TENSE":}
He __________ (not/agree) with your opinion.

• did not agree
• does not agree
• not agree

Answer explanation

In negative sentences, we use "does not" + base verb for singular subjects. The verb remains in base form after "does not."

^{Choose the correct form of the verb in "SIMPLE PRESENT TENSE":}
______your brother _____(know) the answer?

• Does ,knows

• Do , know

• Does , know

Answer explanation

For singular subjects, we use "Does" + subject + base verb.

^{Choose the correct form of the verb in "SIMPLE PRESENT TENSE":}
Every morning, the baby __________ (cry) for milk.

• cry

• crying
• cries

Answer explanation

When a verb ends in "-y" and is preceded by a consonant (cry → cries), we change "y" to "i" and add "es."

^{Choose the correct form of the verb in "SIMPLE PRESENT TENSE":}
She __________ (not/believe) in luck.

• doesn't believe

• does not believe
• does not believes

Answer explanation

"She" is singular, so we use "does not" + base verb (without -s).

^{Choose the correct form of the verb in "SIMPLE PRESENT TENSE":}
Where _____she_____ (live)?

• does, live

• do, lives

• does, lives

Answer explanation

In wh-questions, "does" is used for singular subjects, followed by the base verb.

^{Choose the correct form of the verb in "SIMPLE PRESENT TENSE":}
A flock of birds __________ (fly) over the lake.

• flys
• flying
• flies

Answer explanation

"A flock of birds" is a singular collective noun, so we use "flies" instead of "fly." Singular subjects take verbs ending in "-s" or "-es."

^{Choose the correct form of the verb in "SIMPLE PRESENT TENSE":}
This machine __________ (not/work) properly.

• does not work
• is not working

• does not works

Answer explanation

"This machine" is singular, so we use "does not" + base verb.

^{Choose the correct form of the verb in "SIMPLE PRESENT TENSE":}
What time _____ the train_____ (arrive)?

• does, arrive

• do, arrives

• does, arriving

Answer explanation

The train" is singular, so we use "does" + base verb.

^{Choose the correct form of the verb in "SIMPLE PRESENT TENSE":}
The teacher __________ (explain) the topic well.

• explain
• explained
• explains

Answer explanation

"The teacher" is singular, so we add "-s."