A lot of is x are: Qual utilizar

Hi everyone, I need some help with these two sentences... Shoud I use the verb in the plural or in the singular??

A lot of rice IS grown in Vietnam / or / A lot of rice ARE grown in Vietnam.
A lot of sheep IS raised in New Zealand / or / A lot of sheep ARE raised in New Zealand.

Thanks a lot.
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Avatar do usuário Ricardo F. Bernardi 8790 16 163
You should read:
(1) https://jakubmarian.com/a-lot-of-is-vs-a-lot-of-are-in-english/
(2) https://www.quora.com/There-are-a-lot-of-bags-There-is-a-lot-of-rice-Why-do-we-use-%E2%80%9Cis%E2%80%9D-in-the-second-sentence-instead-of-%E2%80%9Care%E2%80%9D-Is-this-because-rice-is-%E2%80%9Cnone-countable%E2%80%9D

Rice is an uncountable noun.

A lot of rice is grown in Vietnam.
A lot of rice are grown in Vietnam.

Sheep is a countable noun with an irregular plural. We make a habit of counting sheep, before sleep.
By the way, sleep is uncountable.

A lot of sheep is raised in New Zealand.
A lot of sheep are raised in New Zealand.

There is a sheep on the farm.
There are five sheep on the farm.
There are a lot of sheep on the farm.