This mandatory 'Go ahead or turn left' (B21d) traffic sign in France gives a direct instruction you must follow. It's crucial for understanding lane discipline and directions. When you see this sign, you are obliged to proceed either straight ahead or turn left, depending on the arrow's depiction. Always ensure you are in the correct lane and signal clearly to comply with this mandatory directive from the French Code de la route.
This mandatory sign (B21d) dictates that you must proceed straight ahead or make a left turn, offering no other directional choice. Mastering this sign's interpretation is crucial for your French theory test revision and safe navigation.
Mandatory signs tell road users what they must do rather than what they must avoid. This sign can control direction of travel, required lanes, special routes for buses or trams, pedestrian or cycle facilities, snow chains, or minimum speed. A learner should read the sign early, confirm whether it applies to their vehicle, and follow the required movement smoothly. Official French sign code: B21d.
"Go ahead or turn left" gives a positive instruction that the driver or named road user must follow. It may require a direction, lane, path, minimum speed, equipment, or reserved route.
Get clear, practical answers to the most common questions about the B21d - Go ahead or turn left road sign. Learn how the sign works, what rules it represents, and how it affects real driving situations. This FAQ strengthens your understanding and supports accurate decision making for the French driving theory exam in France.
The B21d sign is a mandatory direction sign. It means you must follow the direction indicated by the arrow, which will be either straight ahead or to the left. You cannot choose to turn right or go in any other direction not shown.
You are prohibited from choosing a different movement than the one indicated by the B21d sign. This means you cannot turn right, make a U-turn if not indicated, or deviate from the path shown by the arrow. You also cannot ignore it and proceed as if the sign wasn't there.
The obligation indicated by the B21d sign applies from the point where the sign is placed, or from the point indicated by road markings and the layout of the road ahead. You should be aware of it as soon as you see it and prepare to comply.
You must smoothly follow the indicated direction (ahead or left) by checking your mirrors and signalling appropriately. A common exam trap is confusing this with a 'turn left only' sign; the B21d allows for going straight as well. Ensure you don't mistakenly try to turn right or ignore the directive, as this will result in a theory test failure.
A clear reference image of the B21d - Go ahead or turn left road sign used in France.
The B21d - Go ahead or turn left road sign may also be known by these alternative names or terms.
The B21d - Go ahead or turn left road sign is part of the France Mandatory Signs category, which groups together signs with similar rules and functions.
Comparing signs like 'Go ahead or turn left' with similar mandatory directions helps build strong recall for your French theory test revision. Practicing this traffic sign comparison improves your ability to distinguish subtle differences, reducing exam errors.
The B21-1 'Turn Right' sign: your mandatory direction in France.
The B21b 'Ahead Only' Sign: A Mandatory Direction You Must Follow
The B21c 'Turn Left Ahead' Sign: Your Mandatory Direction
Now that you've reviewed the full list of French road signs, enhance your understanding. Explore signs grouped by specific categories for deeper insights, test your recognition with practice questions, and solidify your knowledge for the Code de la route exam.
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