You are making progress in drawing. Please ___ doing your best.a) keep backb) keep inc) keep awayd) keep on

To determine the best option to fill in the blank in the sentence "You are making progress in drawing. Please ___ doing your best," we can analyze the choices provided:

1. keep back - This phrase typically means to remain at a distance or not to advance towards something. It does not fit well in the context of encouraging someone to continue their efforts.

2. keep in - This phrase is not commonly used in a way that fits the context of the sentence. It may imply something different and does not convey the idea of continuing a positive action.

3. keep away - This suggests maintaining a distance from something, which does not match the context of encouraging continued effort in drawing.

4. keep on - This phrase means to continue doing something and fits perfectly with the context of encouraging someone to persist in their efforts.

Conclusion

Based on the analysis, the best choice to complete the sentence is: d) keep on.

The full sentence would read: "You are making progress in drawing. Please keep on doing your best." This maintains a motivational tone and encourages ongoing effort.