Understanding English Conditional Sentences and Modal Verbs

English Conditional Sentences

Conditional Sentences:

Type 1: Present Simple + Future Simple

This conditional expresses a condition that is likely to occur. The structure is: if + present simple, future simple. This indicates that if the condition is met, the result will happen. You can also use modal verbs or imperatives in the result clause.

Example: If I feel better later, we will go shopping together.

Type 2: Past Simple + Would + Verb

This type expresses hypothetical conditions referring to the present, which are unlikely to occur. Could and might can also be used.

Example: I would read more books if I had spare time.

Type 3: Past Perfect + Would Have + Past Participle

This conditional refers to something impossible in the past that cannot be changed.

Example: If you had not been so busy, we would have met.

Defining and Non-Defining Relative Clauses

Relative Clauses: Defining vs. Non-Defining

Defining Relative Clauses (Restrictive)

These clauses provide essential information to identify the noun they modify. Common relative pronouns include:

• Who: Refers to people.
• Which: Refers to objects.
• When: Refers to moments in time.
• Where: Refers to places.
• Whose: Refers to possession.
• What: Used when the antecedent is omitted. Example: Forget what I wanted to tell you.
• Whom: Used after prepositions, but the preposition is often omitted and placed after the verb.

Non-Defining Relative Clauses (Non-Restrictive)

These clauses provide additional information that is not essential. They are set off by commas and cannot omit the relative pronoun.

Modal Verbs

Modal Verbs:

Can / Be Able To

• Can: Expresses abilities, capacity, making requests, asking for permission, and indicating possibility.
• Be Able To: Expresses abilities and can be used in tenses where "can" is not available.

Cannot / Could

• Cannot: Expresses impossibility, lack of ability, prohibition, and negative deductions.
• Could: Expresses abilities or requests in the past, or more polite suggestions than "can".

May / Might

• May / Might: Express possibility.
• In interrogative form, "May" is a polite way to ask for something.

Would

Used to politely ask someone to do something.

Must / Have To

• Must / Have To: Express obligations. "Must" is primarily used in the present, while "have to" can be used in other tenses.

Need To / Needn't To

• Need To: Expresses obligations and requirements.
• Needn't To: Expresses the absence of obligations and requirements.

Musn't / Don't Have To

• Musn't: Expresses prohibitions.
• Don't Have To: Indicates the absence of obligations and requirements.

Should

Expresses advice or opinion.

Modal Perfect Verbs

Modal Perfect Verbs:

Must Have + Past Participle

Expresses a logical conclusion about something done in the past.

May / Might Have + Past Participle

Used to make assumptions about something in the past.

Could Have + Past Participle

Expresses certainty that something did not occur.

Would Have + Past Participle

Indicates something one would have done in the past but did not, possibly due to external factors.

Should / Ought To Have + Past Participle

Expresses regret about something that occurred or did not occur as desired.

Should Not Have + Past Participle

Expresses criticism about a past action, indicating what should have occurred.

Needn't Have + Past Participle

Indicates that there was no need to do something that was done.