is planting flowers in the garden.
(subject – who, which,
that)It is flowers that Sheila is planting in the garden. (object - that)
It is in the garden that Sheila is planting flowers. (adverbial phrase - that)
She cares only about money.
All (that) she cares about is money.
Jogging keeps me in shape.
What keeps me in shape is jogging.
Jogging is what keeps me in shape.
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