If you (brush )your teeth three times a day , you (not/ have ) cavities.
If the play (be) a success they (start ) a big tour in the whole country.
If my husband ( not/ mow) the lawn , I (have ) to do it myself!​

1. If you brush your teeth three times a day, you will not have cavities.

Explanation: This sentence is using the first conditional to talk about a hypothetical situation. The first part of the sentence "If you brush your teeth three times a day" is the condition, and the second part "you will not have cavities" is the result or consequence of that condition. The speaker is suggesting that if the person brushes their teeth three times a day, they will be able to prevent cavities.

Step-by-step explanation:

- The first part of the sentence introduces the condition: "If you brush your teeth three times a day."
- The second part of the sentence states the result or consequence: "you will not have cavities."
- To form the future result, we use the modal verb "will" + the base form of the verb "have."

2. If the play is a success, they will start a big tour in the whole country.

Explanation: This sentence also uses the first conditional to talk about a hypothetical situation. The first part of the sentence "If the play is a success" is the condition, and the second part "they will start a big tour in the whole country" is the result or consequence of that condition. The speaker is suggesting that if the play is successful, the performers will embark on a tour throughout the entire country.

Step-by-step explanation:

- The first part of the sentence introduces the condition: "If the play is a success."
- The second part of the sentence states the result or consequence: "they will start a big tour in the whole country."
- To form the future result, we use the modal verb "will" + the base form of the verb "start."

3. If my husband does not mow the lawn, I will have to do it myself!

Explanation: This sentence also uses the first conditional to talk about a hypothetical situation. The first part of the sentence "If my husband does not mow the lawn" is the condition, and the second part "I will have to do it myself!" is the result or consequence of that condition. The speaker is suggesting that if the husband doesn't mow the lawn, the speaker will be responsible for doing it herself.

Step-by-step explanation:

- The first part of the sentence introduces the condition: "If my husband does not mow the lawn."
- The second part of the sentence states the result or consequence: "I will have to do it myself!"
- To form the future result, we use the modal verb "will" + the base form of the verb "have to."