Infinitive : - In grammar , the infinitive is the form of a verb that has no inflection to indicate person , number , mood or tense . By far , the most common form of an infinitive in English language is with the particle ' to ' , such as ' to walk ' ' to cry ' etc . This is known as ' to - infinitive ' . It can function as a subject , direct object , subject complement , adjective , or adverb in a sentence .

Infinitive and the Gerund : It will be noticed that the Infinitive and the Gerund are alike in being used as Nouns, while still retaining the power that a Verb has of governing another noun or pronoun in the objective case.

Definition : A Gerund is that form of the verb which ends in – ing, and has the force of a Noun and a verb.

As both the Gerund and the Infinitive have the force of a Noun and a Verb, they have the same uses. Thus in many sentences either of them may be used without any special difference in meaning; as,

• Teach me to swim.

In the question : -

1. Eva is having trouble _________ on the exam.

In this sentence , the correct gerund that can be  placed in the blank part is concentrating .

2. Jim stopped _________ his shoelace. Wait for him.

In this sentence , the correct infinitive that can be  placed in the blank part is to tie .

Thus , the Correct Option is B , which is 1. Concentrating 2. To tie .

Infinitive : - In grammar , the infinitive is the form of a verb that has no inflection to indicate person , number , mood or tense . By far , the most common form of an infinitive in English language is with the particle ' to ' , such as ' to walk ' ' to cry ' etc . This is known as ' to - infinitive ' . It can function as a subject , direct object , subject complement , adjective , or adverb in a sentence .

Infinitive and the Gerund : It will be noticed that the Infinitive and the Gerund are alike in being used as Nouns, while still retaining the power that a Verb has of governing another noun or pronoun in the objective case.

Definition : A Gerund is that form of the verb which ends in – ing, and has the force of a Noun and a verb.

As both the Gerund and the Infinitive have the force of a Noun and a Verb, they have the same uses. Thus in many sentences either of them may be used without any special difference in meaning; as,

• Teach me to swim.

In the question : -

1. Don’t waste my time ___________ about your salary.

In this sentence , the correct gerund that can be  placed in the blank part is complaining .

2. Please allow me ____________ your Facebook page.

In this sentence , the correct infinitive that can be  placed in the blank part is to join .

Thus , the Correct Option is D , which is  1. Complaining 2. To Join .

Infinitive : - In grammar , the infinitive is the form of a verb that has no inflection to indicate person , number , mood or tense . By far , the most common form of an infinitive in English language is with the particle ' to ' , such as ' to walk ' ' to cry ' etc . This is known as ' to - infinitive ' . It can function as a subject , direct object , subject complement , adjective , or adverb in a sentence .

Infinitive and the Gerund : It will be noticed that the Infinitive and the Gerund are alike in being used as Nouns, while still retaining the power that a Verb has of governing another noun or pronoun in the objective case.

Definition : A Gerund is that form of the verb which ends in – ing, and has the force of a Noun and a verb.

As both the Gerund and the Infinitive have the force of a Noun and a Verb, they have the same uses. Thus in many sentences either of them may be used without any special difference in meaning; as,

• Teach me to swim.

In the question : -

He anticipates ____________ trouble with his supervisor. In this sentence , the correct infinitive that can be  placed in the blank part is having as it uses with main verb anticipates .

Thus , the Correct Option is D , which is Having .