Fill in the following blanks with suitable words :
Light travels in _________ lines.

Answer

To fill in the blank in the statement "Light travels in _________ lines," we need to understand how light behaves.

### Step-by-Step Solution:

1. **Understanding Light Travel**: Light is a form of energy that travels from one point to another. It does not bend or curve in a uniform medium unless influenced by external factors.

2. **Observation of Light**: When we observe light from a source, such as a candle, it travels in a specific direction. If there are no obstacles, we can see the light clearly.

3. **Defining the Path of Light**: The path that light takes can be described as a straight line. This is because, in a uniform medium (like air), light travels in a straight path.

4. **Filling the Blank**: Therefore, the correct word to fill in the blank is "straight." The complete statement is: "Light travels in straight lines."

### Final Answer:
Light travels in **straight** lines.