Question

highlight the subordinating conjunction (\swabi\) in the sentence.
because sheldon plankton forgot to cover the blender, his smoothie exploded all over the kitchen.

Explanation:

Subordinating conjunctions (like those in the "SWABI" mnemonic - Since, When, After, Because, If) introduce subordinate clauses. In the given sentence, "Because" introduces the subordinate clause explaining the reason for the smoothie exploding, so it's the subordinating conjunction.

Answer:

Because