Understanding how infinitives work in a sentence is essential for giving clear instructions, sharing suggestions, and expressing goals in English. The position of an infinitive — whether it appears before or after the verb — determines its grammatical role, and mastering this distinction will help you communicate more effectively in professional and everyday contexts.

What is the difference between a subject and a complement?

The key distinction lies in word order. When a word or phrase appears before the verb, it functions as the subject of the sentence. When it appears after the verb, it works as the complement [0:20].

For example:

• Subject: To smoke is forbidden on the plane.
• Complement: My goal is to graduate college in five years.

An important pattern to remember is the use of "it" as an introductory word for infinitive subjects [0:44]. Instead of saying "To smoke is forbidden on the plane," you can rephrase it as "It is forbidden to smoke on the plane." Both sentences carry the exact same meaning — the infinitive still acts as the subject, but the sentence sounds more natural in everyday English.

How can you use infinitives to give instructions and suggestions?

One of the most practical uses of infinitives as subjects and complements is giving instructions and suggestions [1:05]. This is especially useful in professional settings like kitchens, hospitals, and offices.

Here are some examples from real-world contexts:

• Kitchen: "Crush the garlic cloves to peel them easily."
• Kitchen: "It is advised to remove all metallic elements to heat the food."
• Hospital: "Wash hands with water and soap to enter the surgery room" [3:34].
• Office: "It is mandatory to show ID to enter the office building" [3:06].
• Hotel: "The front desk's number is necessary to ask for room service" [2:46].

Notice how each infinitive either explains a purpose (why you do something) or states a requirement (what is necessary or advised).

How do you organize steps using infinitives?

When describing a sequence of actions, infinitives help connect each step to its purpose [1:28]. Consider the example of opening a restaurant:

1. "Use the keys to open the doors to the restaurant."
2. "Look for the switch to turn on the light."
3. "Make a list of groceries to know which ones to buy."
4. "Go to the supermarket to buy the food."
5. "It is important to wash the food before you cook it."
6. "Use the dishes to serve."

Each sentence pairs an action with its goal, making the instructions logical and easy to follow.

What patterns should you remember?

Three common structures appear throughout these examples:

• "It is + adjective + to + verb" — used for general advice or rules. Examples include "It is important to wash," "It is mandatory to show," and "It is advised to remove" [3:51].
• "Verb + object + to + verb" — used to explain purpose. For instance, "Use the keys to open the doors."
• "Noun + is + to + verb" — used to define goals or roles. For example, "My goal is to graduate college in five years" [4:12].

These patterns are versatile and appear constantly in professional communication, written instructions, and academic contexts.

How can you practice infinitives in your daily life?

Think about your own goals and the instructions you give or receive regularly. Try forming sentences like "My goal is to..." or "It is important to..." using real situations from your work or studies. What is your goal when you finish a course or project? Can you give advice to a colleague using an infinitive structure? Share your answers and practice turning everyday ideas into well-structured sentences with infinitives.