1) How to clean up a spill on Shabbos?

2) Grapes vs Strawberries 

3) Making a lemon tea on Shabbos?

4) Washing up on Shabbos?

After the stalks of wheat were sheaved they were brought to fields and threshed, which is the removal of the grain kernels from their chaff.

The basic concept of threshing is extracting fruit or vegetable from its natural inedible shell, peel or similar attachment, eg breaking apart kernels of wheat from the stems.

This melacha applies to plant life and human life, eg expressing human milk or milking an animal, or crushing a honeycomb to extract honey are problems.

Other examples of this melacha are:

Removing peas from the pods or squeezing grapes for their juice.

Squeezing is related to threshing as the juice is extracted from the solid fruit in the same way that grain is detached from husk and peas extracted from their inedible pods.

There are 3 conditions under which one can extract liquids:

1) to improve food

2) squeezing liquids into solid foods

3) sucking fruits/vegetables

Grapes and olives are in a stricter category and dont follow these exemptions, so you can't squeeze then onto a solid food nor can you suck out the juice. It's best to not even cut up fresh grapes or olives onto a plate as it's inevitable that juice will flow out. 

Fruits commonly pressed for their juices, such as orange, lemon, apple and strawberry you can suck out the juice with your mouth, cut them on a plate, squeeze over a solid food, put them in tea, scrape it out with a spoon, or by lemon squeeze it over sugar which can then be stirred into tea, or cut a slice of lemon and place it in the tea. 

But you can't press it against a glass for the juice to come out, eg lemon against a glass, nor slice the fruit over the tea.

Also, squeezing a wet cloth or sponge or any wet fabric to expel absorbed liquid is the melacha, or even to press down on a soaked cloth. Best way to deal with a spill on a tablecloth is to gently use a spoon to pick up not yet observed liquid..or use a plastic table cloth😉. Other methods are to use a rag or towel, just don't wring it out.

To wash dishes on shabbos, you can't use a sponge as the scrubbing exerts pressure and consequently the water will be squeezed out. 

You can use a sponge that has a handle and to then wipe gently. 

Or use a brush with stiff synthetic material or of plastic or wire mesh.

Expressing milk for a baby is also an issue.

A mother who needs to express milk on shabbos should use a hand pump, put liquid soap into a cup and it that way the milk will be unusable.