Can you put instances in a table?

I'm making a shark bite game but instead of the shark being played by a human its gonna be played by a robot and I'm adding them to a table so that I can detect when they all die so the round can end, but when I tried putting them in a table it didn't really work, So can anyone help me?

local sharks = {}

for i, shark  in pairs(workspace:WaitForChild("Sharks"):GetChildren()) do
	if shark then
		table.insert(sharks, shark)
	end
end

local sharks = {}

for i, shark  in pairs(workspace:WaitForChild("Sharks"):GetChildren()) do
    if shark then
        table.insert(sharks, shark)
    end
end

You can add instances into a table your code is right but

I think the folder might have no shark so

when it saids

if shark then

It might not have a shark in that folder

so nothing might be added but other than that your code is fine

I think the problem is at the "if shark then"