Subject-verb agreement

The subject still controls the verb:

• This university (singular), which is made up of many students, teachers, and others, is (singular subject) large.
• The colours (plural) of a gas spectrum tell  (plural form) of its chemical composition.
• The effect (singular) which these reactions caused during the last three weeks is (singular form) insignificant.

• Krypton and neon (they – plural) are noble gases.
• Salt and pepper (they – plural) are always on the table.

However, if two subjects are thought of as a single thing, then use a singular verb. For example:

• Fish and chips (considered one item i.e. singular) is my favourite dish.

• Salt (singular) or pepper (singular) is (singular form) always on the table.
• Real estate (singular) or securities (plural) are (plural form as 2 items) a suitable investment at this time.
• Neither stocks (plural) nor real estate (singular) is (singular form) a good investment at the moment.

• There are (plural) four students (plural) in my presentation group and we will discuss the marketing plan.
• There is (singular) a single main idea (singular) in my first paragraph.

This is especially true for subjects and disciplines, and for illnesses.

• Physics (singular) is the science of matter and energy.
• Diabetes (singular) is a terrible disease.
• Other singular words in these categories include economics, electronics, mathematics, measles, mumps and shingles.

• Four grams of magnesium was used in the chemical experiment.

• Everything in chemistry is explainable in atomic terms and widely explored in the literature.

• Many of my fellow students are ready for their presentations today.
• Few things at university are more valuable than making good friends.

• My family is very supportive of my studies here.

However, they may also take plural verbs. For example:

• My family are very supportive of my studies here.

Which is correct? 

Often it depends on how you think of the group: ‘My family’ as a single unit, or ‘My’ family as several individuals. Other collective nouns like this include team, class, cohort, government, crowd and orchestra.

The best guide is to look at the object of the preposition:

• None of this material (singular) is suitable for industrial applications.
• None of these materials (plural) are suitable for industrial applications.

This is for books, movies, songs, stories, and the like:

• The Regulations of the Senate (singular) is a very important document in Australian politics and has a distinguished history.
• The Annals of the Australian Historical Society (singular) is edited by Dr Proctor.