Mistakes in using one word for another when they are similar in spelling but different in meaning are easily made.

When editing, or simply reading, business documents drafted in English I have noted that certain pairs of words that are pronounced or spelt similarly are frequently confused – even at times by native English writers! Some of the most common mistakes are discussed below.

Enquire / Inquire

Traditionally, enquire (enquiry) and inquire (inquiry) are acceptable alternative spellings of the same word. Interestingly, usage has evolved differently in America and the UK. In America, inquiry now tends to be used for all purposes, and enquiry (enquire) is very rarely seen. In the UK, however, a distinction has developed between the two spellings: to enquire (enquiry) is used to mean “to ask a question”, while an inquiry is an investigation. You might, therefore, enquire what time the inquiry begins.

Despite extensive inquiries there is still no really conclusive proof.
A public inquiry was held into a controversial redevelopment scheme.
The media called for a public inquiry.
A police spokesman said “we are carrying out extensive inquiries to establish the identity of the victim.”
If you wish to know more about our products, please fill in our enquiry form.
General enquiries – please call xxxxx. Technical enquiries – please call yyyyy.
I would like to enquire about membership of your organisation.

Affect / Effect

To affect means to change in some way. Depending on the context, it may mean to delay or stop, to hinder, to prevent, to reduce the effectiveness of or to reduce or increase funds. For example:

Work on the building has been affected by bad weather.
…any fact or event that may affect the Borrower’s financial situation.
Share prices may be affected by political events.

The use of effect instead of affect is a common mistake, very probably caused by the similarity in pronunciation.

To effect means to bring about or accomplish. It is more usually used as a noun, in which case effect means the result or consequence of something. Thus:

This contract enters into effect on 1 January.
The parties agree to the following, with effect from 1 January.
… or if any change in law has the effect of increasing the cost of financing the loan.

Alternate(ly) / Alternative(ly)

Alternate(ly) means to succeed each other by turns (to “take it in turns”).

They worked and rested alternately means at times they worked, then they rested, then they worked again, etc.
The monthly meetings will be chaired alternately by John and Jane.
… alternately high and low noise levels.

Alternately, you can opt for our special luxury package is NOT CORRECT, as presumably the customer is not expected to switch from one product to the other and then back again – here, alternatively should have been used.

Alternative(ly) refers to a choice between two possibilities, or something that can be used instead of something else. For example:

… an alternative solution means that one solution has already been proposed, this is another solution.
We are faced with two alternatives…
The conference centre is located just off the A23. A road map is enclosed. Alternatively, you can travel by train…

Alternative is also something of a “vogue word”, and is used to describe a different way of living or methods that are different from the accepted norm. For example “alternative energy” refers to energy derived from the sun or the wind; “alternative medicine” refers to the use of homeopathic or traditional remedies or methods. Other examples include “alternative society”, “alternative technology” and “alternative cinema”.