1)Over the past ten years, this area (experience) severe fIooding.

2)Houses (damage) and roads (destroy).

3)The local authority (decide) to introduce a fIood control system.

4)At present our workforce (build) a dam on the west side of the town and dikes along the river bank (heighten).

5)We must complete the work within two months, so at present we (work) 24 hours a day.

6)We (believe) that these measures will solve the problem in the short term but on 1st May we (start) work on a new watercourse.

7)The plans already (draw up) and we (be) ready to start next week.

1) Over the past ten years, this area has experienced severe flooding.

Explanation: The phrase "over the past ten years" indicates a period of time in the past. The verb "experience" is the present perfect tense, which is used to describe actions or situations that started in the past and are still relevant in the present. Therefore, it means that the area has experienced severe flooding continuously during the past ten years.

2) Houses have been damaged and roads have been destroyed.

Explanation: The verb "damage" is in the present perfect tense and passive voice, indicating that houses have undergone damage. Similarly, the verb "destroy" is in the present perfect tense and passive voice, indicating that roads have been destroyed. The passive voice implies that someone or something has caused the damage and destruction, but it doesn't specify who or what.

3) The local authority has decided to introduce a flood control system.

Explanation: The verb "decide" is in the present perfect tense, indicating that the local authority made a decision in the past, and this decision is still relevant in the present. The action is to introduce a flood control system, meaning that the local authority has chosen to implement measures to prevent or reduce flooding in the area.

4) At present, our workforce is building a dam on the west side of the town, and dikes along the river bank are being heightened.

Explanation: The phrase "at present" indicates the current ongoing action. The verb "build" is in the present continuous tense, indicating that the workforce is currently engaged in constructing a dam. Additionally, the phrase "are being heightened" suggests that the dikes are currently in the process of being raised or increased in height.

5) We must complete the work within two months, so at present, we are working 24 hours a day.

Explanation: The phrase "must complete" expresses a requirement or obligation to finish the work within two months. The verb "work" is in the present continuous tense, indicating the present ongoing action of working. The statement "we are working 24 hours a day" suggests a continuous and intense effort to complete the work on time.

6) We believe that these measures will solve the problem in the short term, but on 1st May, we will start work on a new watercourse.

Explanation: The verb "believe" is in the present simple tense, indicating a general truth or belief. It states that the speaker (or the group represented by "we") holds the belief that the measures being implemented will effectively address the problem of flooding in the short term. Furthermore, the future action of starting work on a new watercourse is expressed using the future simple tense, highlighting a planned action to begin on 1st May.

7) The plans have already been drawn up, and we will be ready to start next week.

Explanation: The verb "draw up" is in the present perfect tense and passive voice, indicating that the plans have been prepared in the past. The passive voice suggests that someone has created the plans, but it doesn't specify who. The phrase "we will be ready to start" indicates a future action, implying that the necessary preparations will be completed by the specified time, allowing the work to commence.