A hypothesis is a testable explanation to a question or problem. It must be an answer to the question or problem being posed, but must also be testable through conducting an experiment. Your hypothesis should also be specific. It should tell exactly what you think will happen and under what specific conditions.
A hypothesis is easy to write. You can use an "if...then..." format, which will help you show under what conditions you expect certain results. Thus, your hypothesis in an "if...then..." format will be testable. For instance, if your question is "Under what conditions do plants show the greatest growth?" and you were testing plant growth under light and dark conditions, your hypothesis might read like this:
If plants receive sunlight daily, then they will grow at an optimum rate.
To be specific, you might consider which variables you are wishing to test. If, for instance, you are examining plant growth under certain conditions, such as type of liquid received, you would want to explain which type of liquid would produce the best growth. If you are examining the amount of water that plants receive, then your hypothesis should include the amount of water that would produce the best growth. For example:
If plants receive 5 ounces of water daily, then they will grow at an optimum rate.
Or, maybe you are interested in the specific amount of growth shown by the plants. In writing the hypothesis, you should state the specific amount of growth that you expect. For example:
If plants receive 5 ounces of water daily, then they will grow 1 inch over a seven-day period.
Remember to stick to facts when writing your hypothesis as science never tests opinions. The hypothesis should be written so that anyone could design an experiment to test what you think will happen.