English Corner 8: gerunds and participles

It is easy to confuse gerunds with participles since both are verbal forms ending in ing, yet they have different functions; the former being a verbal noun and the latter a verbal adjective.
• Two examples in which explaining is used as a gerund and a participle, respectively, are [He rejected the possibility of a theory’s explaining how osmolytes control volume regulation] and [He rejected the possibility of a theory explaining how osmolytes control volume regulation]. They differ only in the presence of an apostrophe in the first sentence, which indicates the genitive and thus the possession of a following noun (here the gerund explaining). (The genitive is often a sign that a gerund is referred to.)
• In the first sentence, involving the verbal noun (gerund), the possibility of a specific theory (one that explains a role for osmolytes) is rejected. In the second sentence, lacking the apostrophe, explaining is used as a verbal adjective (a participle) to describe the theory. Hence the possibility of any theory is rejected altogether (even one that explains a role for osmolytes).

Gerunds and participles can be distinguished by applying any of the following tests.

Adding the and of either side of the –ing word
• It is a gerund if adding the words the and of either side of the -ing word makes sense or is still grammatical.
• The sentence [Flying planes is dangerous] becomes [The flying of planes is dangerous], which makes sense, so flying here is a gerund [a verbal noun (planes being flown) as subject of the verb are].
By contrast [Flying planes are dangerous] becomes [The flying of planes are dangerous] which has a mismatch of subject (singular) and verb (plural), so flying here is a participle (a verbal adjective describing planes that are in the air).
• Similarly [We passed the professor cycling up the hill] becomes [We passed the professor the cycling of up the hill] which makes no sense, indicating that cycling here is a participle (a verbal adjective describing the professor who was on his bicycle).

Removing the –ing word
• It is a participle if omitting the –ing word does not alter the meaning of the remaining sentence.
• [We passed the professor cycling up the hill] becomes [We passed the professor], in which the meaning is unchanged, so cycling is a participle (a verbal adjective describing the professor).
• Similarly with [Flying planes are dangerous] which becomes [Planes are dangerous], the meaning is also unchanged, so flying is a participle (a verbal adjective describing planes).
• However, [Flying planes is dangerous] becomes [Planes is dangerous], where the agreement in number of subject and verb is violated, so flying here is a gerund (a verbal noun as subject of the verb is).

Changing the sentence order
• It is a participle if changing the sentence around, so that what governed the –ing verb becomes the subject, does not alter the meaning.
• [I saw her wearing a lab-coat] becomes [She was seen wearing a lab-coat], in which the meaning is unchanged, so wearing is a participle (a verbal adjective describing the woman).
• However, [We were surprised by her wearing a lab-coat] becomes [She surprised us wearing a lab-coat] where the meaning is changed (we are now wearing lab-coats), so wearing here is a gerund (a verbal noun possessed by her). Note the genitive (her) and gerund (wearing) together.

By Dr Trevor G Cooper (ctrevorg@gmail.com)