**Rule:** The Future Perfect Tense (will have + past participle) is used to talk about an action that will be completed or a total that will be reached by a certain time in the future. If he fails next week, the total number of failures will reach three. This completion of a total is expressed with the future perfect. Option (b) just states the future failure, but not the cumulative number.

**Rule:** This question tests tense consistency. The reason for the present situation ('We can't get a table') is a past action (or lack thereof). The failure to make a reservation happened in the past. Therefore, the Simple Past Tense ('didn't make') is required. The other options refer to the future, which doesn't explain the current problem.

**Rule:** This question tests tense logic. The result ('should be with you tomorrow') depends on a completed past action. The Present Perfect Passive ('has been sent') is used to describe a recent past action with a result in the present/future. The parcel has already been dispatched. The other options are grammatically incorrect in this context.

**Rule:** The Future Perfect Passive voice (will have been + past participle) is required here. The subject 'our order' receives the action. The action will be completed by a specific future deadline ('by Monday at the latest'). The verb 'assures' signals a promise about a completed future action.

**Rule:** This question tests logical deduction about a past event with present evidence. The modal verb of deduction 'must have' + past participle is used to express a strong conclusion about the past. The present evidence is 'the lights are off'. The conclusion is that they have already left for their holiday. The other options refer to the future, which doesn't fit the evidence.

**Rule**: The **Past Continuous Tense** is used for a longer, ongoing action that was interrupted by a shorter one. **Correct Usage**: The ongoing speech ('was giving') was interrupted by the protestors ('interrupted'). **Incorrect Options**: (a) 'gave' suggests he finished the speech. (c) 'had given' means the speech was already over. (d) 'had been giving' would emphasize the duration before the interruption.

**Rule**: This question, though in a 'Past Tenses' quiz, requires a present tense. The **Present Perfect Continuous Tense** is used for an action that started in the past and is still continuing. **Correct Usage**: 'has been getting' correctly describes the trend of warming that started 'for many decades' and continues up to the present moment ('now'). This is an exception to the 'past tense only' rule to test careful reading. **Incorrect Options**: (a), (c), and (d) are incorrect because the process is stated to be continuing 'now'.

**Rule**: **Dynamic vs. Stative Verbs**. While 'taste' is often a stative verb (describing quality, e.g., 'The soup tastes good'), it can be a **dynamic verb** when it refers to the action of testing something. **Correct Usage**: Here, 'is tasting' refers to the chef's action of sampling the food at this moment. The word 'now' confirms this is an action in progress. **Incorrect Options**: (a) 'tastes' would be used to describe the quality of the food, not the action. (c) 'has tasted' refers to a completed action. (d) 'taste' is the base form.

**Rule**: The **Present Perfect Tense** can be used to report recent news or a recent accomplishment. The exact time is not important; the focus is on the achievement itself. **Correct Usage**: 'has passed' correctly reports the news of his success. While Simple Past ('passed') is also very common here, Present Perfect is used to emphasize the recentness and the current relevance of the news. **Incorrect Options**: (a) 'passes' (Simple Present) is a habit. (b) 'is passing' (Present Continuous) is for an action in progress. (d) 'pass' is a plural verb.

**Rule**: The **Simple Present Tense** is used to describe a person's profession or their usual type of work. **Correct Usage**: 'writes' correctly describes the author's general habit or genre. The subject 'This author' is singular. **Incorrect Options**: (a) 'is writing' (Present Continuous) is for a current project. (c) 'has written' (Present Perfect) refers to her body of work up to now. (d) 'write' is a plural verb.