Understanding Prepositions for Time Ranges

The original sentence is "The interview will be conducted by 9 a.m. till 11 a.m." The underlined segment is "by 9 a.m. till 11 a.m." We need to select the most appropriate option to substitute this segment to correctly indicate the duration of the interview.

Analyzing the Original Phrase

The phrase "by 9 a.m. till 11 a.m." is grammatically incorrect when describing a time range or duration. Let's look at why:

• The preposition 'by' usually indicates a deadline (e.g., "Submit the report by 5 p.m.") or the agent performing an action (e.g., "The work was done by him"). It is not used to indicate the start of a time range.
• The word 'till' (or 'until') indicates the end point of a period. While 'till' can be used correctly in some contexts, pairing 'by' with 'till' to show a time range is not standard English usage.

Therefore, the underlined segment needs to be substituted.

Evaluating the Options

Let's examine each substitution option provided:

Option 1: from 9 a.m. until 11 a.m

• This option uses the pair "from... until".
• "From" correctly indicates the starting point of a time range.
• "Until" correctly indicates the ending point of a time range.
• The structure "from [start time] until [end time]" is a grammatically correct way to specify a duration.

Option 2: during 9 a.m. till 11 a.m.

• This option uses "during... till".
• The preposition "during" is typically followed by a noun phrase indicating a period (e.g., "during the meeting," "during the morning"). It is not usually followed by specific times like "9 a.m. till 11 a.m." in this manner.
• The combination "during [start time] till [end time]" is not standard English for specifying a time range.

Option 3: from 9 a.m. to 11 a.m

• This option uses the pair "from... to".
• "From" correctly indicates the starting point.
• "To" correctly indicates the ending point.
• The structure "from [start time] to [end time]" is the most common and standard way to specify a time range or duration in English.

Option 4: No substitution

• As analyzed above, the original phrase "by 9 a.m. till 11 a.m." is grammatically incorrect for indicating a time range.
• Therefore, substitution is necessary.

Determining the Most Appropriate Option

Both "from 9 a.m. until 11 a.m" (Option 1) and "from 9 a.m. to 11 a.m" (Option 3) are grammatically correct ways to express the time range. However, "from... to" is generally the more standard and widely used construction for this purpose. Given the options, "from 9 a.m. to 11 a.m" is the most appropriate and common substitute.

Therefore, the phrase "from 9 a.m. to 11 a.m" is the best substitution for the underlined segment.

Revision Table: Time Prepositions

Additional Information: Time Prepositions in Sentences

Prepositions of time are crucial for specifying when something happens, its duration, or its timing relative to other events. Choosing the correct preposition helps ensure clarity and grammatical accuracy.

• When indicating a specific point in time, 'at' is used.
• When referring to periods like parts of the day (morning, afternoon, evening), months, years, or seasons, 'in' is typically used. However, for 'night', 'at' is common (at night).
• For days and dates, 'on' is the correct preposition.
• To show a duration with clear start and end points, the pairs 'from... to' or 'from... until' are standard. 'From... to' is generally preferred for simple time spans.
• 'During' is used to indicate that something happens throughout a specific period, often named by a noun.

Mastering these prepositions helps in constructing accurate and natural-sounding English sentences, especially when discussing schedules, events, or processes.