Explanation

 He is very careful. He does not allow his children to drive his car in rush hour traffic.

وہ بہت محتاط ہے۔ وہ اپنے بچوں کو رش کے اوقات میں گاڑی چلانے کی اجازت نہیں دیتا۔

The sentence is in the present tense — indicated by: "He is very careful..."

So, the next part must also be in the present tense.

Explanation

He gave up smoking last year.

اس نے پچھلے سال سگریٹ نوشی ترک کر دی تھی۔

The phrase "last year" indicates a past action

The correct past tense of "give up" is "gave up"

Explanation

He goes to college daily in time.

The subject "He" is third person singular, so in the present simple tense, we add -s to the verb. 

The sentence describes a habitual action, so the present simple tense is appropriate.

Explanation

 "Call on" means to visit someone, especially formally.

So:

"Mr. Steward will call on you at 8.00 P.M."

مسٹر اسٹیورڈ آپ سے شام 8 بجے ملاقات کریں گے۔

Explanation

The sentence describes a past continuous action interrupted by another past action.

So:

"He was sleeping when the doorbell rang."

جب دروازے کی گھنٹی بجی، وہ سو رہا تھا۔

Explanation

This is a scientific fact, so we use simple present tense.

Water boils at 100°C.

پانی 100 ڈگری سینٹی گریڈ پر اُبلتا ہے۔

Explanation

He had his breakfast at 9 o’clock.

The sentence refers to a specific time in the past ("at 9 o’clock"), so the correct tense is simple past.

"Had" is the simple past tense of "have," and it fits well with a completed past action at a specific time.

Explanation

I hope they will not have left the city before I reach there.

مجھے امید ہے کہ میرے وہاں پہنچنے سے پہلے وہ شہر چھوڑ کر نہیں گئے ہوں گے۔

The sentence talks about a future action ("before I reach there") 

Future completed action is the future perfect:

will not have + past participle

"Will not have left" shows:

A completed action in the future

That you hope they are still there when you arrive

Explanation

I buried him two days ago.

The phrase “two days ago” clearly indicates a specific time in the past, so we must use the simple past tense.

"Buried" is the simple past form of the verb "bury."

Explanation

I have been helping him for many years.

میں کئی سالوں سے اس کی مدد کر رہا ہوں۔

The sentence uses "for many years", which indicates an action that started in the past and is still continuing.

For such cases, we use the present perfect continuous tense:

$Subject+have/hasbeen+verb-ing$